1. Field of the Invention
The present invention relates to a computer control system and, more particularly, to a dual path computer control system for regulating the operation of a peripheral device associated with a computer system.
2. Description of Related Art
Computer users have long recognized the need for controlling peripheral devices associated with a computer system. Prior control systems were limited, however, due to certain limitations inherent to computer systems. Computer systems have traditionally been designed as single task systems. In such systems, the computer queues jobs to be performed and processes the queued jobs in the order received. If a higher priority job arises, the computer will suspend operations associated with the current job to process the higher priority job. For this reason, computer system control of peripheral devices was often avoided because, in order to exercise control of the peripheral device, other operations such as data processing had to be suspended. This suspension of processing produces lower efficiency in computer processing power and, thus, longer processing time.
Furthermore, computer system control of peripheral devices has typically required software implementation. Such software routines most commonly arise with in connection with keyboard inputs where an operator programs the computer to accept a single keystroke in substitution for a series of key strokes, which series of key strokes orders the computer to perform a predetermined task. The key designated to substitute for this programmed series of steps is often dubbed a "hot key." Several deficiencies accompany the use of the pre-programmed hot key. The first liability associated with the use of the hot key arises in the step requiring the operator to program the machine to accept the single key stroke as a substitute for the series of key commands. While computers have evolved into an almost essential element of modern society, few users have achieved a level of proficiency that would enable them to draft such a program. The second liability associated with the use of the hot key lies in the fact that the computer must process the program initiated by the hot key rather than process a utility program in use at the time the hot key program was initiated. Initiation of the hot key program, therefore, may cause deterioration of the computer's efficiency similar to that associated with suspensions of operations resulting from computer system control of peripheral devices. A third liability associated with use of the hot key program relates to program compatibility. Hot key program are often referred to as "terminate and stay resident programs" because they are loaded into random access memory (or "RAM"). Problems arise when other, non-compatible, software, is loaded into the machine and interferes with the "terminate and stay resident program." While a hot key created out of hardware may avoid many of these liabilities, thus far, a "hardware hot key" has not been developed.
To avoid these problems, many computer systems provided for the control of peripheral devices through an independent interface. A leading example would be the technique in which audio speakers are incorporated into a computer system. Audio speakers are typically utilized to resonate sound signals generated by the computer system. In incorporating an audio speaker into the computer system, manufacturers have either neglected to provide any type of volume control for the audio speaker or have provided a manually operated electro-mechanical volume controller, for example, a potentiometer, which interfaces directly with the audio speaker for the control thereof. However, the use of such electro-mechanical volume controllers tend to increase the cost of the computer system associated therewith since the incorporation of mechanical components into the design of an electronic device tends to increase manufacturing expenses. The use of such volume controllers may also result in reduced efficiency in operating the associated computer system To operate the volume controller, a computer user must physically discontinue data input or other ongoing activities and manually adjust the volume, thereby suspending or delaying other operations in order to operate the volume controller.
Also, such volume controllers lack feedback signals to indicate to the user that proper volume adjustment has been achieved. For example, the computer system may only active the audio speaker periodically. If the user adjusts the audio speaker during an inactive period, no feedback will be received until the next activation of the speaker.